1. Field of the Invention:
The present invention relates to fuel additives for improving the thermal efficiency and other properties of petroleum fuel, e.g. gasoline, light oil, etc. In particular, it relates to fuel additives utilizing an alkaline agent and elements contained in seawater.
2. Description of the Prior Art:
In spark-ignition engines, such as automobile engines, a higher compression rate generally brings about a higher thermal efficiency, a greater horsepower and an increase in fuel efficiency. In ordinary gasoline engines, however, an excessively high compression ratio rather causes an undesirable decrease in thermal efficiency because of abnormal combustion or knocking.
High-octane gasoline having good antiknock quality must therefore be used if both high compression rate and high fuel efficiency are to be achieved. However, high-octane gasoline is generally expensive since they are produced by blending various gasoline additives in substantial quantities.
In addition, the oxidation of gasoline results in the generation of high molecular weight gummy substances that cause a lowering in octane value and a marked deterioration in fuel efficiency. Because of this, it is necessary to add an antioxidant to gasoline before it is marketed.
In the case of light oil, a fuel for diesel engines (compression ignition engines), ignitability of the fuel is important along with its stability and fluidity, and hence high-cetane light oil having a high ignitability is required. However, high-cetane light oil is expensive, in comparison with ordinary light oil.
In addition, as in the case of gasoline, the oxidative degradation of light oil results in the formation of high molecular weight gummy substances which, if generated in large quantities, may impede the supply of the fuel and may block fuel injection nozzles. In order to prevent such problems resulting from its degradation, light oil must be subjected to hydrorefining or the like.
The present inventors have found that certain elements and bases contained in seawater exhibit synergistic effects on the improvement of combustibility, and have developed a gasoline modifier utilizing salts separated from seawater (Japanese patent application Laid-open No. 47,492/1989). The modifier is solid and, upon use, charged directly into a fuel contained in a container. However, when dissolved into a fuel, part of the modifier disperses into the fuel in the form of solid particles, which may cause a blocking problem in engines.
The solid separated from seawater is readily soluble in water. It is however difficult to blend the solid per se into such a fuel as gasoline and light oil since it is insoluble in such fuels. It is possible to dissolve the solid into an alcohol. However, in cases where the solid is dissolved into an alcohol and the resulting alcohol solution is added to such a fuel, the desired effect could hardly be obtained since the alcohol solution could hardly be admixed uniformly with the fuel due to difference in their specific gravity.